Lawn and garden tractors and other off road vehicles may be equipped with mechanical four wheel steering systems having linkages extending between the front and rear wheel steering assemblies. Examples of mechanical four wheel steering systems are shown in U.S. Pat. Nos. 6,131,689 and 6,684,974.Disadvantages of mechanical four wheel steering systems include their additional weight and cost. Mechanical four wheel steering systems also require space under the tractor frame that otherwise might be needed for high capacity mower decks.
Hydraulic four wheel steering systems also have been proposed for lawn and garden tractors and other off road vehicles in order to reduce the weight and number of parts, save cost, and allow for higher capacity mower decks. However, hydraulic four wheel steering systems have steering angles that may become misaligned between the front and rear wheels.
Position sensors and electronic positioning devices have been proposed to align or synchronize the front and rear wheels of lawn and garden tractors and other off road vehicles. However, there is a need for synchronizing system for hydraulic four wheel steering that does not require or include position sensors or electronic positioning devices, and provides a low cost and less complex system to synchronize hydraulic four wheel steering of a lawn and garden tractor or other off road vehicle.